Blanked spectral index maps (left) and its spectral uncertainties (right). Plots for the spectral index maps; (a) corresponds to α_{8.4−5 GHz)} at a resolution of 0.8″ × 0.8″, (c) to α_{(5.0−1.4 GHz)} at a resolution of 1.4″ × 1.4″, and (e) to α_{(1.4 GHz−150 MHz)} at a resolution of 1.4″ × 1.4″. Right: total spectral index error (taking into account Eq. (1)) at the frequencies given by the left image of each one. For more details, see Sect. 3.2.3.